Language Models

In order to understand language models we need to understand structured prediction. If you are familiar with Sentiment Analysis, where given an input text we need to classify it in a binary manner, in this case the output space usually scales in an exponential manner. The output has some structure, for example it could be a tree, it could be a set of words etc… This usually needs an intersection between statistics and computer science....

2 min · Xuanqiang 'Angelo' Huang

Part of Speech Tagging

What is a part of Speech? A part of speech (POS) is a category of words that display similar syntactic behavior, i.e., they play similar roles within the grammatical structure of sentences. It has been known since the Latin era that some categories of words behave similarly (verbs for declination for example). The intuitive take is that knowing a specific part of speech can help understand the meaning of the sentence....

5 min · Xuanqiang 'Angelo' Huang

Introduction to Natural Language Processing

The landscape of NLP was very different in the beginning of the field. “But it must be recognized that the notion ‘probability of a sentence’ is an entirely useless one, under any known interpretation of this term 1968 p 53. Noam Chomsky. Probability was not seen very well (Chomsky has said many wrong things indeed), and linguists were considered useless. Recently deep learning and computational papers are ubiquitous in major conferences in linguistics, e....

2 min · Xuanqiang 'Angelo' Huang

The Exponential Family

This is the generalization of the family of function where Softmax Function belongs. Many many functions are part of this family, most of the distributions that are used in science are part of the exponential family, e.g. beta, Gaussian, Bernoulli, Categorical distribution, Gamma, Beta, Poisson, are all part of the exponential family. The useful thing is the generalization power of this set of functions: if you prove something about this family, you prove it for every distribution that is part of this family....

6 min · Xuanqiang 'Angelo' Huang

Softmax Function

Softmax is one of the most important functions for neural networks. It also has some interesting properties that we list here. This function is part of The Exponential Family, one can also see that the sigmoid function is a particular case of this softmax, just two variables. Sometimes this could be seen as a relaxation of the action potential inspired by neuroscience (See The Neuron for a little bit more about neurons)....

3 min · Xuanqiang 'Angelo' Huang